Well, I personally think that not only the acquisitions are made with the idea of putting Nintendo and specially Sony out of business, I think they are only part of a bigger plan to achieve that.
Part of their bigger strategy of focusing on Game Pass and putting all their games there plus some big 3rd party games there day one. A nonsensical suicidal business plan that implies a huge investment and tons of loses during many years, something that would kill any platform holder that would try it except the only one with huge pockets to assume these loses: Microsoft.
I think their idea with these acquisitions and the 'day one on GP strategy' would be to, if GP would become super successful in Netflix or Spotify levels (many hundreds of millions of subs) to the point it would kill the other business models and subscriptions would replace game and addon sales, then to have themselves basically a monopoly because the other platform holders -and many publishers and devs- couldn't afford to get the massive loses it implies.
That would kill most of their competition, and after having killed them and having a monopoly, then they'd move to a properly profitable business.
So yes, I think their final main goal is to put Sony and other rival platform holders out of business, but I think this acquisition would be only one small piece inside of a huge puzzle that would be their overal strategy to achieve this.
The thing is that the most important piece of the puzzle, which is the success of Gamepass, isn't performing as they intented. It isn't dominating the gaming market monetization and isn't even making the other platform holders to adopt their 'AAA games day one on a game sub' suicidal strategy. In fact, isn't even dominating the game subs market.
And to have the Activision Blizzard piece would help them to compete, but not to the point that would make all that plan work. They would continue behind Sony and GP would continue behind PS Plus.